[PATCH AUTOSEL 5.3 157/203] ACPI: custom_method: fix memory leaks

Sasha Levin
2019-09-22T18:48:27Z

From: Wenwen Wang <wenwen@cs.uga.edu>

[ Upstream commit 03d1571d9513369c17e6848476763ebbd10ec2cb ]

In cm_write(), 'buf' is allocated through kzalloc(). In the following
execution, if an error occurs, 'buf' is not deallocated, leading to memory
leaks. To fix this issue, free 'buf' before returning the error.

Fixes: 526b4af47f44 ("ACPI: Split out custom_method functionality into an own driver")
Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/acpi/custom_method.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/custom_method.c b/drivers/acpi/custom_method.c
index b2ef4c2ec955d..fd66a736621cf 100644
--- a/drivers/acpi/custom_method.c
+++ b/drivers/acpi/custom_method.c
@@ -49,8 +49,10 @@ static ssize_t cm_write(struct file *file, const char __user * user_buf,
if ((*ppos > max_size) ||
(*ppos + count > max_size) ||
(*ppos + count < count) ||
- (count > uncopied_bytes))
+ (count > uncopied_bytes)) {
+ kfree(buf);
return -EINVAL;
+ }

if (copy_from_user(buf + (*ppos), user_buf, count)) {
kfree(buf);
@@ -70,6 +72,7 @@ static ssize_t cm_write(struct file *file, const char __user * user_buf,
add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
}

+ kfree(buf);
return count;
}

--
2.20.1